19
UNI 4 Installation Instructions
10 Installation of external kitchen
hood
If you use an external kitchen hood, follow the
documentation regarding installation and adjusting air flow
rates which is supplied with the hood.
10.1 Kitchen hoods without a motor
(connected to unit)
The ventilation unit has a separate connection point for
kitchen hoods without a motor. Between the unit and the
hood an electrical cable (low-voltage) must be connected
in order to force the air flow in the hood via the switch on the
hood.
10.2 Kitchen hoods with a motor
(not connected to unit)
A kitchen hood with a motor is not installed to the unit. This
has its own duct system for air evacuation.
With the kitchen hood it is possible to compensate for the
amount of air drawn out of the house.
See chapter 10.2 for more information.
11 Adjusting the kitchen hood
If the hood is not supplied by Flexit, the supplier of the
kitchen hood must plan air flow rates both for extraction and
in the hood, and arrange for supply air to the hood.
11.1 Kitchen hoods without a motor
(connected to unit)
The air flow rate over the hood is regulated according to
the planned air flow rate. Flexit’s kitchen hoods handle
odour absorption up to 150 m
³
/h. It is not necessary to
compensate for the supply air fan to achieve a balanced air
flow rate.
11.2 Kitchen hoods with a motor
(not connected to unit)
When using a kitchen hood with a motor, the extract air flow
rate will increase. To compensate for this, the ventilation unit
can be set give a higher supply air flow rate than extract air
flow rate.
A signal to the unit is required when the kitchen hood is used:
1. external switch with OFF/ON signal is to be connected to
3-core cable on unit (SP4-G0, see the circuit diagram).
2. Install the pressure relay (accessory).
It works like this:
The supply air fan will be increased to the maximum stage,
while the extract air fan will continue at the MIN-stage in
order to compensate for the volume of air the cooker hood
evacuates from the building. This is important to balance the
ventilation in the building.
Check the kitchen hood’s maximum air capacity (using
the enclosed capacity diagram) against the maximum
capacity of the air supply fan. If the kitchen hood has a
higher capacity than the unit’s supply air fan, the unit will
not manage to compensate for the loss of air, and sufficient
supply air must be arranged in some other way.
